Jared Graves has been diagnosed with a brain tumor, according to a post on his Instagram account.

Graves is one of the most influential racers in the sport. The Aussie has been a strong presence in BMX, 4X, downhill and enduro disciplines over his long career, racking up an Olympic appearance, four world championships, 21 World Cup and Enduro World Series appearances, and most notably, taking home the 2014 EWS World Champion title. Graves was instrumental in developing many of Yeti’s bikes during his 11 years with the brand. In 2015, he joined Specialized Racing, where he’s been ever since.

Graves is a pillar of the community, and he has the support of the entire mountain bike community behind him as he faces this next battle.